Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: dwp on April 28, 2013, 01:29:13 pm

Title: Help with Soundtech PA Board please
Post by: dwp on April 28, 2013, 01:29:13 pm

sorry not a guitar tube amp but I thought I would try and fix my neighbor kids PA Power supply. This board had come off the stand-offs and pinged the chassis, blew both under the cover 15A fuses, toasted these two resistors. not sure about the other trasistor parts or what they are even but if I could find a safe value on the resistors I would go from there.
Does anyone know where I might find a schematic to a SoundTech PL600? I had no luck on line, other than half the page on a PL500, and it shows the R601 resistor as a 1K. (thats the one that disentegrated and halves are pointing up right now.
Think the other components in the smoke zone could have survived this incident? the other resistor above the 601 is still intact and throwing out a value, but color rings are not legible.
any help will be appreciated, thanks in advance.

Title: Re: Help with Soundtech PA Board please
Post by: HotBluePlates on April 28, 2013, 03:43:18 pm

I'd contact SoundTech (http://www.soundtech.com/contact/) for a schematic. Or for ordering information for a replacement board...

I wouldn't trust that any of the solid-state survived, not sure on the big filter caps. The rectifiers probably came through alright, but you never know. Also, all that charring is now a resistive path between things that shouldn't be connected. At a minimum, it will have to be cleaned/scraped off. At worst, the board might need replacing.